This invention relates generally to bio-electrodes and, more particularly, to methods of making conductive and adhesive lamina for use with and to form such electrodes. The methods and electrodes of this invention are particularly useful for transmitting electrical signals between the patient and peripheral medical equipment for diagnostic or therapeutic purposes and for electro-medical grounding applications.
In the past, a variety of electrodes have been utilized to transmit or receive bio-electric signals in medical applications. These electrodes generally comprise a solid electrical conductor such as a plate, an adapter and lead wire for connection to the medical equipment, and a conductive lamina. The lamina typically consists of a gel, or other membrane which contains an ionic material to conduct signals between the electrode plate and the patient. Such lamina are typically prepared separately and, subsequently, applied and combined with other elements to form the complete electrode.
These prior art, pre-formed lamina are typically expensive and inefficient to manufacture and to use with or to form an electrode. They further are limited as to size, shape and thickness, as well as to the choice of conductive compositions utilized. Also, electrodes utilizing pre-formed lamina often distort transmitted signals because of relative movement between the electrode and the body surface. Further, electrical hot spots may be caused by the separation of the conductive lamina from the electrode plate or from an uneven distribution of electrolyte in the lamina. Conversely, the high degree of adhesiveness of some electrodes can cause skin irritations to some patients. Some electrodes, therefore, utilize pastes, creams, gels or liquids to overcome this problem, but this added procedure is time consuming and messy.
Insofar as is known, no electrode has been made or proposed, having lamina formed directly on an electrode base and electrical connection surface, and which will maintain stable physical characteristics and effective signal transmission characteristics for a clinically necessary time period.